Multi-purpose vehicle mounted soil specific conductivity real-time tester
Technical field
The present invention relates to sensing technology and soil physico-chemical characteristic measuring technique, particularly a kind of multi-purpose vehicle mounted soil specific conductivity real-time tester.
Background technology
Soil conductivity has comprised the abundant information of soil nutrient and physicochemical property, with the soil property that influences crop yield confidential relation is arranged.Obtain soil conductivity information, and merge with the out of Memory data effectively, help estimating the growing environment of crops.
The proving installation of soil conductivity being done in-site measurement mainly contains two kinds of basic mentalities of designing: based on the contactless design of electromagnetic induction principle with based on the contact design of " current-voltage four-end method ".Contactless design has utilized electromagnetic induction principle (EMI), promptly feeds exchange current to the transmitting coil of instrument internal, and responds to the variation in magnetic field in the soil with receiving coil, characterizes the value of soil conductivity by the variation of institute's measuring magnetic field.Based on the typical representative products of the contactless design of electromagnetic induction principle is the EM38 that Canadian Geonics company produces.The product shape of EM38 is strip, and weight is lighter, need not contact soil, inner structure to soil is not destroyed, and can finish measurement to the farmland transversal scanning, but cost an arm and a leg, can't adapt to the widely used needs of domestic agricultural, major applications is studied in scientific experiment.
Comparatively ripe " current-voltage four-end method " theory is adopted in the design of another soil conductivity proving installation, use this theory, when the measured soil conductivity, can not take a sample, do not stir the soil body, keep ortho states original position Continuous Observation, measured value that obtains and soil extraction conductivity value have correlativity preferably.External existing research and development based on this principle soil conductivity testing tool are as the Veris3100 soil conductivity tester of U.S. Veris Technology company production.This tester can be measured the conductivity value in large tracts of land field in the short period of time.But this tester has the following disadvantages:
1, the electrode of tester adopts the disc type design, and this design is had relatively high expectations to edaphic condition, causes electrode damage when sandstone is more in the soil easily;
2, tester can only use during the free time in the farmland, needs most when measuring in plant growth and but can't use;
3, tester does not possess the real-time communication ability with the field computing machine;
4, can only carry out floppy disk storage, the mass data that is unfavorable for preserving gained in the tester;
5, tester costs an arm and a leg, and only is applicable to research, is unfavorable for promoting the use of on a large scale.
Summary of the invention
The objective of the invention is to overcome defectives such as existing soil conductivity testing tool electrode design is unreasonable, the working time is restricted, cost an arm and a leg, the multi-purpose vehicle mounted soil specific conductivity real-time tester of a kind of measuring accuracy height, unrestricted, the suitable China's national situation of Measuring Time is provided.
To achieve these goals, the invention provides a kind of multi-purpose vehicle mounted soil specific conductivity real-time tester, form by electrode sensor unit 16 and data acquisition and processing (DAP) unit 17; Described electrode sensor unit is made up of bracing frame 1, wheel 2 and columnar electrode, and wherein wheel 2 and columnar electrode are fixed on the bracing frame 1; Described data acquisition and processing (DAP) unit comprises power-switching circuit 6, conversion of signals amplifying circuit 7, analog to digital converter 8, processor 9 and liquid crystal display circuit 11; Described data acquisition and processing (DAP) unit 17 is by a polycore cable 13, respectively with described electrode sensor unit on contact conductor electrically connect; It is characterized in that:
Described columnar electrode has 6, is symmetrically distributed along the center line of bracing frame 1, outermost a pair of electrode A 1, A2 for the conductivity that is used for the measured soil deep layer; The most inboard a pair of electrode C1, C2 for the conductivity that is used for the measured soil shallow-layer; That be arranged on bracing frame 1 centre is power output end electrode pair B1, B2, the electrode that each columnar electrode becomes the cylindrical metal of spade to make by front end buries and holds 3, be fixed into one with the rectangular parallelepiped metal connecting piece 4 of hollow tubular, the top of web member 4 is fixed on the bracing frame 1;
Described power-switching circuit 6 links to each other with external power source, the direct current that external power source provided is converted to the power output end electrode pair B1 that is transported to behind the constant current alternating current in the electrode sensor unit 16, B2, through power output end electrode B 1, the continuous current that B2 enters soil forms different voltage drops according to the difference of soil conductivity between the earth difference, voltage detecting electrode A 1 in the columnar electrode, A2, C1, C2 detects the ac voltage signal at electrode two ends, and transmit signals to conversion of signals amplifying circuit 7, ac voltage signal is converted into effective value in conversion of signals amplifying circuit 7, and amplify, enter analog to digital converter 8 then and do analog to digital conversion, the data that obtain after the conversion are admitted to processor 9, in processor 9, do data processing, the interelectrode voltage drop of voltage detecting is converted to the conductivity value of soil.
In the technique scheme, also comprise a LCD, this LCD is electrically connected with the data acquisition and processing (DAP) unit, and resulting soil conductivity value can be presented on the LCD by liquid crystal display circuit (11).
In the technique scheme, described data acquisition and processing (DAP) unit also comprises memory circuit 10, and memory circuit 10 is stored in the soil conductivity result of processor 9 outputs in the external memory storage.
In the technique scheme, described data acquisition and processing (DAP) unit also comprises CAN agreement communicating circuit 12, and CAN agreement communicating circuit 12 sends the conductivity data result to the field computing machine to generate agricultural land soil distribution of conductivity figure.
In the technique scheme, the CAN agreement in the described CAN agreement communicating circuit 12 specifically adopts the CAN2.0B communication standard.
In the technique scheme, described electrode end 3 the pole tip that buries is designed to the double-vane spade, and the inclination angle of burying is 20 degree, and the length and width of double-vane spade pole tip all is 160 millimeters, the center section protuberance of pole tip, and open angle is 27 degree, and the pole tip edge of shovel adopts sharpening down.
In the technique scheme, described electrode buries equidistant between the jack on end 3 and the web member 4, by adjusting the bury matching relationship of the jack on end 3 and the web member 4 of electrode, regulates the height of columnar electrode.
In the technique scheme, when described web member 4 is fixed on the bracing frame 1, be lined with rubber sheet gasket 5 in both junctions, the effect of rubber sheet gasket 5 is to prevent to be short-circuited between each columnar electrode of sensor.
In the technique scheme, in the described processor 9, be provided with voltage and soil conductivity modular converter, the interelectrode voltage drop of voltage detecting is converted to the conductivity value of soil, the transformational relation of described voltage and soil conductivity is a power function relationship curve, parameter in the power function is relevant with the physical construction of the shape of soil and sensor, and the formula that embodies of this power function relationship model is:
Wherein, y is a soil conductivity, and x is the magnitude of voltage that collects, model parameter k
1Be an amount that changes with the electrode sensor structural parameters, model parameter k
2It is the amount that changes with the soil texture.
The invention has the advantages that:
1, the versatility of various cultivation seasons.The present invention can be prior to seeding the farmland can use idle season, prepare to provide the science data in farmland for sowing, also can measure, for the precision management of crop provides science data in crop growing season.
2, electrode pole tip of the present invention adopts the design of double-vane shovel, penetration performance is better, contact closely with soil after burying, it is strong to make the ability of disturbing dry up, has higher measuring accuracy, this electrode has stronger hack, weeding ability simultaneously, can realize weeding, the intertillage function of loosening the soil when measuring deep soil and thin solum conductivity.
3, sensor electrode is reasonable in design, and the present invention uses " current-voltage four-end method " principle, adopts six pillar electrode design, electrode design is reasonable, science, and is solid durable, destroys less to agricultural land soil, owing to adopt split-type design, even therefore the electrode damaged on end that buries is bad also conveniently replaced.
4, the present invention adopts international CAN2.0B communication standard, and data acquisition unit as the CAN intelligent node, is finished the reliable data transmission with the field computing machine.
5, the present invention is provided with on control panel and dials the retaining knob, can adjust the size of constant current source input current according to the difference of survey agricultural land soil moral character.
6, the present invention has possessed the usb data memory function, has realized the quick storage of mass data, adapts to the agricultural engineering need of practice.
7, simple to operate, the safety of the present invention, the data acquisition control unit volume is less, and convenient the installation is suitable for the on-the-spot use in farmland very much.
Description of drawings
Fig. 1 is the structural drawing of multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 2 is the structural drawing of the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 3 a is the electrode of the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention end that buries;
Fig. 3 b is the web member of the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 3 c is the rubber film of the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 3 d is the bracing frame of the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 4 a is the end pole tip synoptic diagram that buries of the electrode in the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 4 b is the bury inclination angle synoptic diagram that buries of end pole tip of the electrode in the electrode sensor unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 5 is the structural drawing of the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 6 is the circuit theory diagrams of the power-switching circuit 6 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 7 is the circuit theory diagrams of the conversion of signals amplifying circuit 7 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 8 is the circuit theory diagrams of the analog to digital conversion circuit 8 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Fig. 9 is the circuit theory diagrams of the memory circuit 10 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Figure 10 is the circuit theory diagrams of the liquid crystal display circuit 11 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention;
Figure 11 is the circuit theory diagrams of the CAN agreement communicating circuit 12 in the data acquisition and processing (DAP) unit in the multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention.
The drawing explanation:
1 bracing frame, 2 wheels, the 3 electrodes end that buries
4 web members, 5 rubber sheet gaskets, 6 power-switching circuits
7 conversion of signals and amplifying circuit 8 analog to digital converters 9 processors
10 memory circuits, 11 liquid crystal display circuit 12CAN agreement communicating circuits
13 cables, 14 plugs, 15 leads
16 electrode sensor unit, 17 a data acquisition and processing (DAP) unit A1 left side first columnar electrode of number
Right several second columnar electrode of several second the columnar electrode B2 in right first columnar electrode of number of A2 B1 left side
Right several the 3rd columnar electrodes of several the 3rd the columnar electrode C2 in a C1 left side
Embodiment
Be described further with regard to multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention below in conjunction with the drawings and specific embodiments.
Multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention is made up of electrode sensor unit 16, data acquisition and processing (DAP) unit 17 two parts.As shown in Figure 1, data acquisition and processing (DAP) unit 17 is by a polycore cable 13, respectively with described electrode sensor unit 16 on contact conductor electrically connect, at the two ends of this cable, a plug is arranged respectively.Cable 13 link to each other with data acquisition and processing (DAP) unit 17 end plug directly be inserted in the corresponding interface of data acquisition and processing (DAP) unit, cable 13 link to each other with electrode sensor unit 16 end plug then tell several leads, every lead is connected separately with electrode in the electrode sensor unit, and the quantity of lead is decided according to the number of electrodes in the electrode sensor unit.In the data acquisition and processing (DAP) unit, also provide interface with external GPS receiver and field computing machine.Described field computing machine is a small computer platforms that is applied to accurate agricultural, and it can be installed in the pilothouse of agricultural machinery, has the good dust-proof shake-proof ability, is the important component part of precision agriculture field information management.In the present embodiment, the Ag170 field computing machine that can adopt Trimble company to produce, this computing machine can be installed in and finish soil sampling in the pilothouse, the operation of field information acquisition and agricultural machinery working navigation.
Shown in Fig. 2, Fig. 3 a-Fig. 3 d, electrode sensor unit 16 comprises bracing frame 1, wheel 2, electrode bury end 3, web member 4 and rubber film 5.
Bracing frame 1 plays the effect of each ingredient of connection electrode sensor in electrode sensor unit 16, bracing frame 1 is a rectangular support, the rear end of bracing frame 1 is used for fixing by electrode bury end 3 and the columnar electrode formed of web member 4, bracing frame 1 front end is a bikini standard hitch, form a leg-of-mutton hanger bracket and be fixed on the bracing frame, fix by pivot pin with the hydraulicefficiency elevation structure at power machine rear portion.In the present embodiment, the length of bracing frame is 185cm, and wide is 61cm.
The a pair of wheel 2 that is being symmetrically distributed at the two ends, the left and right sides of bracing frame 1, its effect are auxiliary electrode sensor unit motions when testing conductivity, and the embedded depth of restriction columnar electrode.Wheel 2 adopts rubber tyre, and its height should be less than the height of columnar electrode.In the present embodiment, wheel 2 is 30cm apart from the distance on bracing frame both sides, and the difference in height of wheel and columnar electrode is 15cm.
Along the axis of bracing frame 1, it is several to columnar electrode to be symmetrically distributed on support member 1, and the main effect of columnar electrode is the measurement that realizes soil conductivity.In the present embodiment, 3 pairs of columnar electrodes are arranged in the electrode sensor unit 16, the high 60cm of each electrode, in these 3 pairs of columnar electrodes that are symmetrically distributed along the axis of bracing frame 1, outermost pair of electrodes A1 and A2 are used for the conductivity value of measured soil deep layer, the most inboard pair of electrodes C1 and C2 are used for the conductivity value of measured soil shallow-layer, and these two pairs of electrodes can be described as the voltage detecting electrode.Middle pair of electrodes B1 and B2 then are the output terminals of constant-current supply.According to the principle of " current-voltage four-end method ", though the height of 6 electrodes is identical, middle electrode as the constant-current supply output terminal can provide a current field at the earth.As shown in Figure 1, because the distribution of field is uneven, therefore, medial electrode can only detect the magnitude of voltage of soil shallow-layer, and lateral electrode can detect the voltage of deep subsoil.In addition, each makes multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention not only can meet the needs that soil conductivity is measured to distance certain at interval between the electrode, can adapt to the capable row spacing degree in wheat, the corn farmland simultaneously fully.
Columnar electrode by electrode bury the end 3 and web member 4 two parts form.Shown in Fig. 4 a, 4b, electrode buries and holds 3 one-tenth spades, and pole tip is sharp, and the inclination angle of burying is 20 degree, and steady operation in various soil properties suits.Electrode end 3 this design of burying makes it except the conductivity measurement function, also has soil intertillage function.In the present embodiment, electrode end 3 the pole tip that buries is designed to the double-vane spade, and its length and width all is 160mm, the center section protuberance, open angle is 27 degree, and the pole tip edge of shovel adopts sharpening down, and the inclination angle of burying is 20 degree, therefore, the bury penetration performance of end of this electrode is good, has stronger hack ability, and the electrode end 3 that buries enters behind the soil buried in soil, contact closely with soil, improved stability and the degree of accuracy of instrument of the present invention when the measured soil conductivity.In addition, also can utilize the bury left and right sides sweepback both wings of end 3 pole tip of electrode to cut off grass roots.The open angle of end 3 double-vane spade pole tips is 27 degree because electrode buries, and has guaranteed that the edge of shovel during grass roots, has sliding cutting preferably in cutting, cuts laborsavingly, and grass roots is not easy to hang on the pole tip.
The electrode end 3 that buries is connected on the bracing frame 1 by web member 4.Web member 4 is rectangular parallelepipeds of a hollow, and web member 4 and electrode bury to hold on 3 and all be distributed with equally spaced several jacks, and the jack spacing is 2cm.When electrode buries end 3 when being connected with web member 4, electrode is buried hold 3 to be inserted in the web member 4, and bolt inserted in the jack to bury with fixed connecting piece 4 and electrode hold 3.Because each jack is equidistant, therefore can adjusts bury end 3 and 4 jacks that mated of web member of electrode and realize adjusting the column electrode height.A foursquare steel plate has been welded on the top of web member 4, is distributed with 4 bolts hole on four jiaos of the steel plates, with an other pitch-row is identical with it on the bracing frame 1 square plate by bolt, to realize fixing between web member 4 and the support member 1.Obviously, by to the tightening and unscrewing of bolt, can realize the position adjustments of web member 4 on bracing frame 1.
When the web member 4 of columnar electrode is connected with bracing frame 1, between the steel plate that both are used to connect, be lined with a rubber sheet gasket 5, the effect of rubber sheet gasket 5 is to prevent to be short-circuited between each columnar electrode of sensor.
The composition of data acquisition and processing (DAP) unit comprises: power-switching circuit 6, conversion of signals amplifying circuit 7, A/D converter 8, processor 9, memory circuit 10, liquid crystal display circuit 11, CAN agreement communicating circuit 12 shown in the inner branch of the frame of broken lines among Fig. 5.Power-switching circuit 6 links to each other with external power source, the direct current that external power source provided is converted to the columnar electrode delivered to behind the constant current alternating current of 300Hz in the electrode sensor unit to B1 and B2, the continuous current that enters soil through B1 and B2 according to soil conductivity difference between the earth difference, form different voltage drops, columnar electrode is to A1, A2 and C1, C2 detects the ac voltage signal at each self-electrode two ends respectively and transmits signals to conversion of signals amplifying circuit 7, ac voltage signal is converted into effective value in conversion of signals amplifying circuit 7, and amplify, enter analog to digital converter 8 then and do analog to digital conversion, the data that obtain after the conversion are admitted to processor 9, in processor 9, do data processing, voltage drop between detecting electrode is converted to the conductivity value of soil, resulting soil conductivity value can be presented on the LCD by liquid crystal display circuit 11, also can be stored on the external USB storer, can also do exchange by CAN agreement communicating circuit 12 and field computing machine by memory circuit 10.
Power-switching circuit 6 has two functions, is for the electron device in the data acquisition and processing (DAP) unit provides operating voltage on the one hand, is on the other hand to link to each other with constant current electrode in the electrode sensor unit, for instrument provides constant current drive.Find under study for action,, influence the accuracy that soil conductivity is measured if constant current drive adopts direct current signal to cause the polarization phenomena of soil intermediate ion easily.But in actual use, external power source is direct supply normally, therefore need convert direct current to alternating current, and power-switching circuit 6 has been realized the conversion from the direct current to the alternating current.In the present embodiment, voltage conversion circuit 6 is converted to the alternation electricity with the 12V direct current that external power source provided, and the frequency size of this electric current is 300 hertz.In addition, because factors such as the conductivity of soil and water cut have bigger related, therefore the size of holding current is that steady state value may cause output distortion and the too small phenomenon of output in whole test process, this is unfavorable for the accurate measurement to soil conductivity, therefore the size of the exchange current that need be provided power-switching circuit 6 is done adjusting, and therefore power-switching circuit 6 of the present invention also has the function of regulating the output current size.
The circuit theory diagrams of power-switching circuit 6 as shown in Figure 6, by this circuit diagram as can be known, the sinusoidal ac that power-switching circuit 6 offers the electrode sensor unit is produced by ICL8038, but this alternating current can not be when load changes, guarantee that current value does not change, therefore also will add the chip that model is LM324 in circuit, the effect of this chip is that the offset of sinusoidal alternating current is done the constant current processing.Power-switching circuit 6 also requires the adjustable size of alternating current, therefore also should comprise an adjustable potentiometer in circuit diagram, represents this adjustable potentiometer with R16 in circuit diagram, by regulating the current value that R16 can change the output sinusoidal alternating current.
Conversion of signals amplifying circuit 7 mainly contains two functions, and the one, after changing into effective value, export from the resulting alternating voltage signal of columnar electrode, the 2nd, the voltage signal that converts effective value to is done amplifieroperation.Accordingly, conversion of signals amplifying circuit 7 can be divided into signal conversion module and signal amplification module, and above-mentioned module realizes aforesaid two functions respectively.As shown in Figure 7, in the present embodiment, the signal conversion module function realizes that by chip AD536 chip AD536 can directly use hardware circuit to convert alternating signal to direct current signal, and the value of the direct current signal after the conversion is exactly the effective value of AC signal.The AD536 chip operation is stable, and slewing rate is fast, and the conversion accuracy height can satisfy the needs of system works fully.It is ripe prior art that signal is done amplifieroperation, in the present embodiment, no longer it is done detailed description.
The effect of A/D (modulus) converter 8 is that analog signal conversion is become digital signal.Conversion of signals amplifying circuit 7 is sent to A/D converter 8 after voltage signal is amplified, and finishes analog-to-digital operation.In the present embodiment, A/D converter 8 can be selected 12 bit serial double channel A/D converter MAX144 for use.The circuit theory diagrams of A/D converter 8 as shown in Figure 8.
The effect of processor 9 is that digital signal is handled.After processor 9 obtained voltage digital signal from A/D converter 8, the relational model according to institute's stored voltage and soil conductivity in the processor converted magnitude of voltage to conductivity.In the relational model of voltage and soil conductivity, voltage signal and conductivity signal are the power function relationship curve, and the parameter in the power function is relevant with the physical construction of the shape of soil and sensor.The formula that embodies of this power function relationship model is:
Wherein, y is a soil conductivity, and x is the magnitude of voltage that collects, model parameter k
1Be an amount that changes with the electrode sensor structural parameters, and model parameter k
2It is the amount that changes with the soil texture.
In the present embodiment, it is the processor of LPC2119 that processor 9 can adopt model, and it is a kind of high-performance 32 digit RISC micro controllers based on ARM7TDMI-S.
Memory circuit 10 is interface circuits of external memory storage, and its effect is with the soil conductivity of processor output quick storage externally in the storer as a result.Memory circuit 10 makes multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention have the usb data memory function, makes the quick storage of mass data be called possibility.The circuit theory diagrams of the memory circuit 10 in the present embodiment as shown in Figure 9.
The effect of liquid crystal display circuit 11 is that the conductivity data result is presented on the LCD.The circuit theory diagrams of the liquid crystal display circuit 11 in the present embodiment as shown in figure 10.
The effect of CAN agreement communicating circuit 12 is to send the conductivity data result to the field computing machine to generate agricultural land soil distribution of conductivity figure.In the present embodiment, the CAN agreement specifically adopts the CAN2.0B communication standard.The circuit theory diagrams of CAN agreement communicating circuit 12 as shown in figure 11.
Except foregoing circuit, data acquisition and processing (DAP) unit 17 also has a control panel, and by this control panel, the operator controls in real time to multi-purpose vehicle mounted soil specific conductivity real-time tester.On control panel, comprise LCDs, power switch, collection switch, communication switch, reset switch and fork shift switch.LCDs adopts mode connected in series to link to each other with liquid crystal display circuit 11, the conductivity value of agricultural land soil can be shown in real time.Power switch is used to control the power supply of multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention.The fork shift switch is used to change the size of alternating current.Gathering switch is used to determine this whether to install operate as normal.Communication switch is used for the determination data collection and whether control module carries out data communication with the field computing machine.Reset switch links to each other with the reseting pin of processor, and the effect of reset switch is when the program run in data acquisition and the control module occurs wrong or needs internal processes to get back to original state, stirs reset switch, gives the processor electrification reset.
Multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention also can an external GPS receiver, this receiver directly links to each other with processor 9 in the data acquisition and processing (DAP) unit, be connected to simultaneously on the outside field computing machine, utilize the GPS receiver can obtain the spatial positional information of multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention when work easily, these information are sent in the processor 9, the conductivity data of the agricultural land soil that is collected with multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention is done fusion, can make the spatial distribution map of agricultural land soil conductivity easily.
The test process of multi-purpose vehicle mounted soil specific conductivity real-time tester of the present invention is as follows:
At first, press the power switch opening power, if display screen shows " system works ", the initialization of expression instrument can operate as normal.Second step, press the collection switch, begin to carry out data acquisition, because the double channel A of selecting for use/D chip by software setting, allows 1 second kind of each passage sample 10 times, 1 second kind sampled result is added up obtain average, send processor to.In the 3rd step, the model algorithm program that processor is embedded will calculate the conductivity value of soil according to the voltage signal that collects, and this data presentation on display screen, and is deposited in the external USB data-carrier store.The 4th step, in the computing machine of field, generate agricultural land soil distribution of conductivity figure if desired, the serial port of field computing machine with the data acquisition and processing (DAP) unit is connected, press communication switch, display screen shows " data transmission ", sends conductivity data to the field computing machine.Mistake in test process, occurs, then can make processor reset, test again by reset switch.Control panel also is provided with the fork shift switch in addition, can regulate the amplitude of constant current source exchange current, to satisfy the needs of real work according to the difference of soil texture structure.